1. Technical Field
The present disclosure relates to lithium ion batteries.
2. Description of Related Art
A lithium ion battery includes a case, an anode, a cathode, a non-aqueous electrolyte, and a separator. The anode, cathode, non-aqueous electrolyte, and separator are encapsulated in the case. The separator is located between the anode and the cathode. The anode, cathode, and separator are infiltrated by the non-aqueous electrolyte. The cathode includes a cathode current collector and a cathode material layer disposed on a surface of the cathode current collector. The anode includes an anode current collector and an anode material layer disposed on a surface of the anode current collector.
The current collector is used to collect the charge generated by the lithium ion battery during discharge, and to connect to an external power source during the recharging of the lithium ion battery. The current collectors are usually made of metal foils, such as copper foil and aluminum foil. However, the metal foils have a relatively large weight. The power density is calculated by power/weight. Therefore, a large weight of the current collector will decrease the power density of a lithium ion battery. Furthermore, the metal foils may be corroded by the electrolyte, which decreases the life span of the lithium ion battery.
What is needed, therefore, is to provide a lithium ion battery having high power density and long life.